Over the past decade, significant advances have been made in novel drug delivery systems. Polyelectrolyte complexation has been studied as a drug delivery vehicle. Polyelectrolyte complexes (PECs) are associative complexes of one or more predominantly positive polyelectrolytes and one or more predominantly negative polyelectrolytes. They are formed due to a combination of electrostatic and entropic interactions between the oppositely charged polyions. This ion pairing is a type of physical crosslinking, which avoids the use of cross-linking agents (e.g., chemical, physical), thereby reducing the possible toxicity and other undesirable effects of the reagents.
Electrospinning is an established technique used to produce non-woven fiber mats for a variety of applications, such as tissue engineering scaffolds, nanofiltration membranes, and battery materials. Electrospun fiber mats are comprised of randomly accumulated nano- or microscale diameter fibers, which have microscale interstitial spacing, large surface-to-volume ratios, high specific surface area, and interconnected porosity. Although mats have been electrospun from over very diverse types of polymers, green processing has remained a challenge. (Dong, et al. J. Power Sources 2011, 196 (11), 4886-4904; Engel, et al. Materials Today 2012, 15 (11), 478-485; Deitzel, J. Polymer 2001, 42 (19), 8163-8170; Ramakrishna, et al. Materials Today 2006, 9 (3), 40-50; Regev, et al. Polymer 2010, 51 (12), 2611-2620.)
While the concept of polyelectrolyte complexes as a drug delivery system and other applications have seen heightened interest in recent years, significant obstacles and challenges remain both in processing technologies and functionalities of the resulting materials. A key challenge is the need for a simple, inexpensive and environmentally friendly processing technique.